The Tennessee Bureau of Investigations has put out a new amber alert to highlight a search for a teacher believed to have kidnapped a 15-year-old student. Bureau agents said they had received tipoffs from 24 states since the disappearance on Monday (13 March) and that the teacher had been added to the state's 10 Most Wanted list on Friday.

Fifteen-year-old Elizabeth Thomas is feared to have been kidnapped by Tad Cummins, 50, a former teacher at her school, authorities said. Cummins' post was terminated by the Maury County school district on Tuesday as part of an investigation into alleged inappropriate contact Cummins had with Thomas earlier in the year.

The bureau said that its investigation suggested "a troubling pattern of behaviour on the part of Cummins" and that the alleged abduction had been planned in advance.

"Nothing investigators have learned about Cummins or his intentions for the young girl since issuing the amber alert calms the imminent concern for Elizabeth's wellbeing. In fact, it only heightens it," investigators said.

Elizabeth is described as a 5ft 5in, white, with hazel eyes and weighing 120lbs. Cummins is a 6ft white male with brown hair and eyes and weighs 200lbs. He drives a silver Nissan Rogue with the Tennessee license plate 976-ZPT and is believed to be armed with two handguns.

Tennessee authorities said they had received 250 tipoffs but said that was a low number, suggesting that the couple may have been sleeping in Cummins' vehicle rather than checking into motels.

"Having now been on the run for more than five days, Cummins may have taken her anywhere," the bureau said.